Always wanted to do an online sudoku script.
A few days ago finally finished it, so I will be very grateful if you can help me, and to tell what good, what bad in the game and design.
There is an original function, you can put note in the cell by pressing right mouse button.

I gave this a quick go. My initial thoughts are that it's very fiddly without having any kind of keyboard input - and that having the numberpad obscure some of the puzzle as you are entering digits is a little annoying. I suspect that your users will also find it very useful to have a "pencilmark" feature for the harder puzzles!

Other than that, I thought the interface was clean, and the puzzles seemed nice enough!